Question

An object is placed 75 cm from a convex lens having a 50 cm focal length.
State the characteristics of the image (real/virtual; upright/inverted)
6.4. Calculate optical power of the lens
6.5. Calculate the distance between the image and the lens
6.6. Calculate the magnification of the image

Answer 1

Explanation:

since object is placed between focus and centre

of curvature ( f = 50cm , u = 75 cm)

=> image is real ,inverted, bigger than the object.

=> optical power of the lens = 1/f(in meter)

= 1/0.5

= 2D

=> distance between image and lens

v =( u×f) /( u-f) = (75×50) / (75-50)

= 150 cm

=> mangification = -v/u = 150/75 = -2

hope this helps you